This section explains how to control a hobby RC servo from an Arduino Uno or Arduino Leonardo that is connected to the Zumo Shield. The Arduino IDE includes a Servo library that generates the pulses needed to control an RC servo. However, this servo library conflicts with the ZumoMotors library in that both rely on Timer 1. Instead, you will need to do something special to get servo control working.
To control a servo with an Arduino Uno, see Section 8.a. To control a servo with an Arduino Leonardo, see Section 8.b.